Netty
· Netty is an asynchronous event-driven network application framework for
rapid development of maintainable high performance protocol servers and
clients.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window netty-parent-4.1.26.Final.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.